Hackers break HD-DVD copy protection

A group of hackers around the world has defeated the anti-piracy software protecting several HD movies in the HD-DVD format.

After cracking the encryption, the group began distributing copies of the films — starting with Universal Pictures’ "Serenity" —using the file-sharing tool, BitTorrent.

A "New York Times" report said the hacking incident could send the technology companies behind the optical formats back to the drawing board to improve their copy protection. It could also prompt Hollywood studios to rethink their alliances in the war between the HD-DVD and Blu-ray formats.

The HD-DVD format, backed by Toshiba, Microsoft and Intel, uses copy protection technology known as the Advanced Access Content System. The rival Blu-ray format, supported by Sony, Hewlett-Packard and Dell, uses the same system but adds a level of software that acts as a backup when the first level is compromised, so it is considered to be slightly more secure.

The latest illegal activity came less than a month after a user named Muslix64 announced in a Web forum that he had broken at least part of the HD-DVD protection system. Muslix64 released free software that allowed users to play HD-DVDs on their computers and make copies of those films without the original encryption. To make it work, however, users still needed a special title key, generated by the AACS software, for each movie they were trying to copy.

Muslix64 did not initially provide the title keys, but the challenge to finish the work was on the table. By last week, dozens of keys for movies such as "King Kong," "Mission Impossible: 3" and "Superman Returns," were posted on various Web forums.

Security experts said that the hackers appeared to have discovered the secret keys on their own computers — stashed there by WinDVD, a commercial program for playing DVDs.